This invention relates to an air heating unit in which air is heated by means of friction, and to a heating and cooling system which uses such an air heating unit.
It is known that a rotating fan rotor can be utilized to frictionally heat air to an elevated temperature, and various prior patents have disclosed applications of this general principle. Note for example the following prior U.S. Pat. Nos. 1,682,102; 3,297,019; 3,245,399; 3,467,179; 3,481,322; 3,958,552; and 3,977,387.
It is an object of the present invention to provide an improved air heating unit in which air is heated by means of friction and which has a number of advantages over the frictional air heating units heretofore proposed.
A more specific object of this invention is to provide a frictional air heating unit which more effectively utilizes all of the energy input for heating the air so as to thereby provide a considerably enhanced operating efficiency.
Another object of this invention is to provide a heating and cooling system suitable for heating or cooling buildings and which utilizes this improved frictional air heating unit.
A further object of this invention is to provide a heating and cooling system of the type described which is also capable of supplying heated water.